I need a firewall because I was decade long user of internet security suites on windows. I am not a professional of networks or anything but a student who just needs to block unblock running applications...
GUFW a simple firewall was a good option but isnt available on Fedora nor any gui firewall & am frustrated over searching it for 2days...
I checked Vuurmuur its powerful but for noobs & if configured wrongly its a great mess (even their documentation forewarns that). Similarly SeLinux is not a firewall

A firewall controls the flow of traffic to and from a computer to the
network. SELinux can confine access of programs within a computer and
hence can be conceptually thought of a internal firewall between
programs

I think its just a way to protect core filesystem nothing more than that ...
So what are my options, please suggest me something some resource that is understandable to a starter & if somehow bugged willn't have irreversible consequences.

Further just tell me if I want to reject in/out traffic for the address(s) containing keyword wolfram e.g pk.server.wolfram or wolfram-mathematica.com how would I do that in iptables or somehow...& if I want to block intenet for application /opt/telepath-gabble how would I achieve that

ufw is very simple to use and has good documentation...
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jasonwryanJan 28 '13 at 6:26

selinux is not about the core filesystem (what ever this is) but about providing acls for application, i.e. this application can connect to the internet or open a specific port, read the filesystem etc.
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Ulrich DangelJan 28 '13 at 8:12

selinux is internal firewall according to official page how come I control (via selinux) any app's access to net
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nightcrawlerJan 28 '13 at 8:22

@nightcrawler, SELinux is not a firewall. It's a mechanism for managing MAC (Mandatory Access Control, a way of setting up policies that are more detailed and which override user set permissions).
–
vonbrandJan 28 '13 at 15:32